WO2024055678A1

WO2024055678A1 - Winding and unwinding system, control method, and preparation device for battery electrode sheet

Info

Publication number: WO2024055678A1
Application number: PCT/CN2023/102736
Authority: WO
Inventors: 罗宇; 吴堃; 肖秋华
Original assignee: 宁德时代新能源科技股份有限公司
Priority date: 2022-09-15
Filing date: 2023-06-27
Publication date: 2024-03-21
Also published as: CN115818304A

Abstract

A winding and unwinding system (100), comprising at least two winding rollers (120), a roll changing device (130), a sensing device (150), a measuring device (140), and a controller. The roll changing device (130) can drive the at least two winding rollers (120) to sequentially move to a set position, and the winding roller (120) located at the set position can wind a strip material; the sensing device (150) sends an in-place signal when the winding roller (120) located at the set position rotates by one circle; the measuring device (140) is used for measuring the running length of the strip material; when receiving the in-place signal, the controller determines, according to the running length measured by the measuring device (140), the winding diameter of the winding roller (120) located at the set position; when the winding diameter reaches a preset threshold, the controller controls the roll changing device (130) to drive the other winding roller (120) to move to the set position and come into contact with the strip material, so that the strip material is wound to the other winding roller (120). Thus, an ultrasonic ranging sensor is removed, the mode of measuring the winding diameter is independent of the thickness of the strip material, and the measuring accuracy is high. Further comprised are a control method for the winding and unwinding system (100), and a preparation device for a battery electrode sheet.

Description

Rewinding and unwinding system, control method and battery pole piece preparation device

cross reference

This application cites Chinese patent application No. 202211124550.5 titled "Rewinding and unwinding system, control method and battery pole piece preparation device" submitted on September 15, 2022, which is fully incorporated into this application by reference.

Technical field

The present application relates to the field of battery technology, and in particular to a rewinding and unwinding system, a control method and a device for preparing battery pole pieces.

Background technique

Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development.

When the battery pole piece is rewinding, in order to achieve taper tension control, the rewinding diameter needs to be detected to adjust the tension according to the rewinding diameter. However, the current common methods of measuring roll diameter have low measurement accuracy.

Contents of the invention

This application aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of this application is to propose a rewinding and unwinding system, a control method and a device for preparing battery pole pieces, so as to improve the measurement accuracy of the rewinding diameter.

The embodiment of the first aspect of the present application provides a rewinding and unwinding system, including: at least two rewinding rollers, a roll changing device, a sensing device, a measuring device and a controller. The roll changing device can drive at least two rewinding rollers to move to the set position in sequence, and the rewinding roller at the set position can rewind the strip; the sensing device sends out a position signal when the rewinding roller at the set position rotates once. ;The measuring device is used to measure the running length of the strip. The controller is connected to the sensing device, the measuring device and the roll changing device. In response to receiving the in-position signal, the controller determines the winding diameter of the winding roller at the set position based on the tape length measured by the measuring device; control When the winding diameter reaches the preset threshold, the roll changing device sends a roll change signal to the roll change device. The roll change device receives the roll change signal and drives the other winding roller to move to the set position and contact the strip, so that the strip roll Wind onto the other take-up roller.

In the technical solution of the embodiment of the present application, by measuring the running length of the strip when the winding roller rotates once, the current circumference of the winding roller can be determined, and then the current winding diameter of the winding roller can be measured. In this way, the ultrasonic distance sensor is omitted, which not only saves costs, but also has high measurement accuracy, which helps avoid misestimation of the number of winding layers due to measurement errors. Moreover, the way in which the winding and unwinding system of this embodiment measures the winding diameter has nothing to do with the thickness and tension of the strip. Therefore, it is not affected by the thickness of the pole piece and the interlayer spacing of the pole piece, and the measurement accuracy is high.

In some embodiments, the sensing device includes a light-emitting device and a receiving device. The light-emitting device is used to emit photoelectric signals, and the receiving device is used to receive photoelectric signals. When the winding roller at a set position rotates for one revolution, the receiving device responds to the photoelectric signals. Receive status changes and send out a signal in place. With this arrangement, the sensing device is a photoelectric switch, which has the advantage of high detection accuracy.

In some embodiments, the light-emitting device and the receiving device are fixed and arranged oppositely, and a light-shielding member is installed on the winding roller at a set position. The light-shielding member can rotate with the winding roller to between the light-emitting device and the receiving device and block the light-emitting device. Photoelectric signal. With this arrangement, the sensing device sends out an in-position signal according to the rotation of the winding roller, and cooperates with the controller for measurement.

In some embodiments, the sensing device is a slot photoelectric switch or a through-beam photoelectric switch. By setting the slot-type sensing device as a slot-type photoelectric switch or a through-beam photoelectric switch, it can be easily obtained through purchase, and the light-emitting device and the receiving device are integrated into a single component, eliminating the need for separate installation.

In some embodiments, the rewinding and unwinding system further includes a traction mechanism, which is located upstream of the rewinding roller along the conveying direction of the strip to pull the strip and transport it to the rewinding roller at a set position. The traction mechanism can be used to apply traction force to the strip to transport the strip in a direction close to the winding roller.

In some embodiments, the traction mechanism includes a traction motor, an active traction roller and a driven traction roller. The active traction roller is drivingly connected to the traction motor, and the strip passes between the active traction roller and the driven traction roller; the measuring device measures the active traction roller. The rotation angle or rotational displacement of the traction roller or the driven traction roller determines the length of the strip.

In some embodiments, the measuring device is a meter wheel, and the meter wheel is in contact with the surface of the active traction roller or the driven traction roller. In this embodiment, the meter wheel is arranged to be in contact with the surface of the active traction roller or the driven traction roller to detect the rotational displacement of the active traction roller or the driven traction roller, thereby directly determining the running length of the strip without the need for Conversion requires little calculation. Moreover, compared with the meter wheel being in contact with the surface of the strip to measure the running length of the strip, in this embodiment the meter wheel is not in contact with the strip to prevent the meter wheel from contacting the active material layer on the strip. The strip may be affected by contact.

In some embodiments, it also includes a driving device and a roll-changing pressure roller that is drivingly connected to the driving device. The driving device is connected to a controller; the controller sends a rolling signal to the driving device when the winding diameter reaches a preset threshold, and the driving device The device receives the roll pressing signal and drives the roll changing pressure roller to move close to the set position so that the roll changing pressure roller contacts the strip. Set up like this After changing the roll, the new winding roller winds up the strip, and the changing pressure roller can move to contact the strip to exert pressure on the strip to ensure that the strip can be wound onto the new winding roller.

In some embodiments, the driving device includes a swing arm and a servo motor. One end of the swing arm is connected to the roll changing pressure roller, the other end of the swing arm is drivingly connected to the servo motor, and the servo motor is connected to the controller.

In some embodiments, the winding and unwinding system further includes a unwinding roller, which is used to unwind the strip. The unwinding roller is located upstream of the winding roller along the conveying direction of the strip.

Compared with the measurement of the winding diameter by the ultrasonic distance sensor, the measurement accuracy of the winding and unwinding system of this embodiment is high. Therefore, it is helpful to avoid measuring the number of layers of the strip wound on the unwinding roller due to measurement errors. Wrong estimation, thus helping to avoid waste caused by automatic roll change of the unwinding roller in advance.

An embodiment of the second aspect of the application provides a device for preparing battery pole pieces, which includes the rewinding and unwinding system provided by the embodiment of the first aspect of the application.

The third embodiment of the present application provides a rewinding and unwinding control method, which is suitable for the rewinding and unwinding system provided by the first embodiment of the present application. The control method includes: acquiring an in-position signal; in response to receiving the in-position signal, Determine the winding diameter of the winding roller at the set position based on the tape length measured by the measuring device; when the winding diameter reaches the preset threshold, a roll change signal is sent to the roll change device to control the roll change device to drive it The other winding roller moves to the set position and contacts the strip, causing the strip to be wound onto the other winding roller.

In some embodiments, after determining the winding diameter of the winding roller at the set position based on the tape length measured by the measuring device, the control method further includes: when the winding diameter reaches a preset threshold, the control method sends a signal to the driving device when the winding diameter reaches a preset threshold. Send a roll pressing signal to control the driving device to drive the roll changing pressure roller to move close to the set position so that the roll changing pressure roller contacts the strip.

The above description is only an overview of the technical solutions of the present application. In order to have a clearer understanding of the technical means of the present application, they can be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and understandable. , the specific implementation methods of the present application are specifically listed below.

Description of drawings

In the drawings, unless otherwise specified, the same reference numbers refer to the same or similar parts or elements throughout the several figures. The drawings are not necessarily to scale. It should be understood that these drawings depict only some embodiments disclosed in accordance with the present application and should not be considered as limiting the scope of the present application. In order to explain the technical solutions of the embodiments of the present application more clearly, the drawings required to be used in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. Those of ordinary skill in the art can also obtain other drawings based on the drawings without exerting creative efforts.

Figure 1 is a schematic diagram of a rewinding and unwinding system in a related example;

Figure 2 is a schematic diagram of another rewinding and unwinding system in a related example;

Figure 3 is a schematic diagram of a rewinding and unwinding system in a first working state according to an embodiment of the present application;

Figure 4 is a schematic diagram of a rewinding and unwinding system in a second working state according to an embodiment of the present application;

Figure 5 is a schematic diagram of a rewinding and unwinding system in a third working state according to an embodiment of the present application;

Figure 6 is a schematic diagram of another rewinding and unwinding system in the first working state according to the embodiment of the present application;

Figure 7 is a schematic diagram of another rewinding and unwinding system in the second working state according to the embodiment of the present application;

Figure 8 is a schematic diagram of another rewinding and unwinding system in the third working state according to the embodiment of the present application;

Figure 9 is a schematic flow chart of a rewinding and unwinding control method according to an embodiment of the present application.

Explanation of reference symbols:
100-Rewinding and unwinding system;
110-unwinding roller; 111-third motor;
120-winding roller;
130-roll changing device; 131-machine base; 132-rod body; 133-turntable;
140-measuring device; 141-fixed seat; 142-connecting rod; 143-cylinder;
150-Induction device; 151-Light-emitting device; 152-Receiving device;
160-traction mechanism; 161-active traction roller; 162-driven traction roller; 163-traction motor;
170-roll changing pressure roller; 171-driving device; 1711-servo motor; 1712-swing arm;
200-strip.

Detailed ways

The embodiments of the technical solution of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only used to illustrate the technical solution of the present application more clearly, and are therefore only used as examples and cannot be used to limit the protection scope of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the technical field belonging to this application; the terms used herein are for the purpose of describing specific embodiments only and are not intended to be used in Limitation of this application; the terms "including" and "having" and any variations thereof in the description and claims of this application and the above description of the drawings are intended to cover non-exclusive inclusion.

In the description of the embodiments of this application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying the relative importance or implicitly indicating the quantity or specificity of the indicated technical features. order Or primary and secondary relationship. In the description of the embodiments of this application, "plurality" means two or more, unless otherwise explicitly and specifically limited.

Reference herein to "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearances of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those skilled in the art understand, both explicitly and implicitly, that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of this application, the term "and/or" is only an association relationship describing associated objects, indicating that there can be three relationships, such as A and/or B, which can mean: A exists alone, and A exists simultaneously and B, there are three cases of B alone. In addition, the character "/" in this article generally indicates that the related objects are an "or" relationship.

In the description of the embodiments of this application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to It is more than two pieces (including two pieces).

In the description of the embodiments of this application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right" and "vertical" The orientation or positional relationships indicated by "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on those shown in the accompanying drawings. The orientation or positional relationship is only for the convenience of describing the embodiments of the present application and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the implementation of the present application. Example limitations.

In the description of the embodiments of this application, unless otherwise clearly stated and limited, technical terms such as "installation", "connection", "connection" and "fixing" should be understood in a broad sense. For example, it can be a fixed connection or a removable connection. It can be disassembled and connected, or integrated; it can also be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two elements or an interaction between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

Batteries are widely used in energy storage power systems, electric vehicles, military equipment, aerospace and other fields. The battery mainly includes an electrode assembly. As the power storage part, the electrode assembly is mainly composed of a positive electrode plate, a negative electrode plate and a separator. The battery mainly relies on the movement of metal ions between the positive electrode plate and the negative electrode plate to work. Both the positive electrode piece and the negative electrode piece include a current collector and an active material layer, and the active material layer is coated on the surface of the current collector. Among them, the production process of the pole piece is usually as follows: using coating equipment to coat the active material layer on the pole piece, the pole piece coated with the active material layer is transported to the pressing roller device, and the pressing roller device presses the pole piece to The current collector and active material layer are compressed, and then the pole piece is continuously transported to the winding roller for winding.

When a constant tension is used for winding, as the winding diameter increases, the outer pole piece easily slips and slides along the axial direction of the winding roller, and the inner pole piece close to the winding roller is prone to wrinkles. In order to solve this problem, it is usually necessary to implement taper tension control during rewinding, that is, the tension is adjusted based on changes in the rewinding diameter, and the tension is reduced when the rewinding diameter increases. Therefore, the winding diameter needs to be measured.

Figure 1 is a schematic diagram of a rewinding and unwinding system in a related example. In some examples, as shown in Figure 1, the ultrasonic distance sensor 180a can be used to directly detect the winding diameter. In this example, the working principle of measuring the winding diameter is: the center of the ultrasonic distance sensor 180a and the winding roller 120a The distance is a fixed value L1, and the ultrasonic distance sensor 180a can detect the distance L2 between it and the winding roller 120a, then the winding diameter is L1-L2. However, there are the following problems in using the ultrasonic distance sensor 180a to detect the winding diameter: first, the cost of the ultrasonic distance sensor 180a is high; second, the detection accuracy of the ultrasonic distance sensor 180a is ±0.5mm, while the pole piece 200a The thickness is usually 4 to 6 micrometers (μm). In this way, when there is an error in the detection of the ultrasonic distance sensor 180a, such as -0.5 millimeters (mm), the theoretical number of layers of the winding roller 120a winding pole piece 200a is calculated based on this. It is much larger than the actual number of layers of the pole piece 200a wound up by the winding roller 120a, and the number of layers of the pole piece 200a wound up by the winding roller 120a is misestimated. When the diameter of the winding roller 120a is equal to the diameter of the unwinding roller, the number of layers of the winding roller 120a that winds up the pole piece 200a is equal to the number of layers of the unwinding roller that unwinds the pole piece 200a. Correspondingly, the calculated unwinding roller The theoretical number of layers of the unwinding pole piece 200a is much greater than the actual number of layers of the unwinding pole piece 200a of the unwinding roller, which leads to an incorrect estimation of the actual number of layers of the unwinding roller pole piece 200a, which in turn causes the unwinding roller to automatically change the roll. causing waste.

Figure 2 is a schematic diagram of another rewinding and unwinding system in a related example. In other examples, as shown in Figure 2, the rewinding and unwinding system 100a includes a rewinding roller 110a, a rewinding roller 120a, a thickness measuring device 190a, a proximity switch 150a and a counter 191a. The unwinding roller 110a is used to unwind the pole piece. 200a, the winding roller 120a is used to wind up the pole piece 200a. Along the conveying direction of the pole piece 200a, the thickness measuring device 190a is located downstream of the unwinding roller 110a and is used to measure the thickness h of the pole piece 200a. The proximity switch 150a is used to When the unwinding roller 110a winds around once, it sends a signal to the counter 191a, and the counter 191a counts in response to receiving the signal. Taking the diameter of the winding roller 120a as equal to the diameter of the unwinding roller 110a as an example, the working principle of measuring the winding roll diameter in this example is: every time the unwinding roller 110a rotates once, the unwinding roll diameter decreases by 2h. The initial diameter of the winding roller 110a is D0. When the number of rotations of the unwinding roller 110a reaches N, the unwinding roll diameter R=(D0-2hN)/2. Correspondingly, the winding diameter r=(D0+2hN)/2. However, due to the accuracy limitation of the pressure roller device and the limitation of the coating process, the thickness of the pole piece 200a is uneven. Therefore, when this method is used to detect the winding diameter, the thickness of the pole piece 200a will affect the accuracy of the calculation of the roll diameter.

In view of this, the applicant proposed a rewinding and unwinding system that uses a measuring device to measure the length of the strip when the rewinding roller rotates once, and thereby can determine the circumference of the rewinding roller. length, so that the winding diameter of the winding roller can be calculated.

The rewinding and unwinding system disclosed in the embodiment of the present application can be applied to the rewinding of various types of strips. For example, the strip material may refer to the pole piece of the battery. Specifically, the strip material may be a positive pole piece or a negative pole piece; or the strip material may also refer to a steel sheet, an adhesive tape, a cloth tape, or a paper tape. In this embodiment There are no restrictions on this. When the strip is a pole piece, the strip may specifically include a metal foil (such as copper foil or aluminum foil) and an active material layer. The rewinding and unwinding system at this time may be used in the die-cutting process of the pole piece.

Figure 3 is a schematic diagram of a rewinding and unwinding system provided by an embodiment of the present application in a first working state. Figure 4 is a schematic diagram of a rewinding and unwinding system provided by an embodiment of the present application in a second working state. Figure 5 This is a schematic diagram of a rewinding and unwinding system in the third working state provided by the embodiment of the present application. Referring to FIGS. 3 to 5 , according to some embodiments of the present application, the rewinding and unwinding system 100 includes at least two rewinding rollers 120 , a roll changing device 130 , a sensing device 150 , a measuring device 140 and a controller. The roll changing device 130 can drive at least two winding rollers 120 to move to the set position in sequence. The winding roller 120 located at the set position can wind up the strip 200. The sensing device 150 rotates when the winding roller 120 located at the set position An in-position signal is sent out when one revolution is completed, and the measuring device 140 is used to measure the running length of the strip 200 .

The controller is connected to the sensing device 150, the measuring device 140 and the roll changing device 130. In response to receiving the in-position signal, the controller determines the winding of the winding roller 120 at the set position based on the tape length measured by the measuring device 140. Roll diameter; when the winding diameter reaches the preset threshold, the controller sends a roll change signal to the roll change device 130. The roll change device 130 receives the roll change signal and drives the other winding roller 120 to move to the set position and interact with the belt. The strip 200 is in contact with each other, so that the strip 200 is wound onto the other winding roller 120 .

The winding and unwinding system 100 may include a first motor and a second motor. The first motor is used to drive the winding roller 120 at a set position to rotate. The strip 200 rotates with the winding roller 120 to be wound to the winding roller 120 superior.

The working principle of measuring the winding diameter in this embodiment is: when the winding roller 120 at the set position rotates once, the sensing device 150 sends an in-position signal. At this time, the controller determines the tape length measured by the measuring device 140 That is the current circumference C of the winding roller 120. According to the circumference calculation formula C=2πr, the current winding diameter r of the winding roller 120 can be measured. The winding diameter r refers to the winding radius.

When it is determined that the winding diameter r reaches the preset threshold, it can be used to indicate that the winding diameter r is close to or reaches the maximum winding diameter. At this time, the winding and unwinding system 100 can automatically change the winding roller 120. The principle of rolling The controller sends a roll change signal to the roll change device 130, and the roll change device 130 receives the roll change signal to drive the other winding roller 120 to move. to the set position and in contact with the strip 200, and the second motor is used to drive the other winding roller 120 that moves to the set position to rotate. The strip 200 can rotate with the other winding roller 120 to be wound to another On a winding roller 120.

Taking two winding rollers 120 as an example, the roll changing device 130 can be as shown in Figures 3 to 5, for example. The roll changing device 130 includes a machine base 131 and a rod body 132. The machine base 131 is installed on the ground, and the rod body 132 can be On the rotating installation base 131, two rewinding rollers 120 are connected to both ends of the rod 132 respectively. When the rewinding and unwinding system 100 is in the first working state, one of the rewinding rollers 120 is in the set position, and the roll changing device 130 After receiving the roll change signal, the rod 132 rotates to cause the other winding roller 120 to move to the set position.

FIG. 6 is a schematic diagram of another rewinding and unwinding system 100 provided by an embodiment of the present application in a first working state. FIG. 7 is a schematic diagram of another rewinding and unwinding system 100 provided by an embodiment of the present application in a second working state. Schematic diagram. FIG. 8 is a schematic diagram of another rewinding and unwinding system 100 in the third working state according to the embodiment of the present application. Or, in other embodiments, as shown in FIGS. 6 to 8 , the roll changing device 130 may also include a turntable 133 , one end of the two winding rollers 120 is connected to the turntable 133 , and the turntable 133 rotates to change the two winding rollers. The position of the roller 120 is such that the two winding rollers 120 can move to the set position in sequence.

In summary, the rewinding and unwinding system 100 of this embodiment can determine the current circumference of the rewinding roller 120 by measuring the running length of the strip 200 when the rewinding roller 120 rotates once, and further can measure the current circumference of the rewinding roller 120. The winding diameter. In this way, the ultrasonic distance sensor is omitted, which not only saves costs, but also has high measurement accuracy, which helps avoid misestimation of the number of winding layers due to measurement errors. Moreover, the way the rewinding and unwinding system 100 of this embodiment measures the rewinding diameter has nothing to do with the thickness and tension of the strip 200. Therefore, it is not affected by the thickness of the pole piece and the interlayer spacing of the pole piece, and the measurement accuracy is high. .

In addition, the rewinding and unwinding system 100 is also designed to automatically replace the rewinding roller 120 by controlling the roll changing device 130 when the rewinding diameter reaches a preset threshold, so that the new rewinding roller 120 moves to the set position. Winding up the strip 200, the strip 200 is automatically wound onto the winding roller 120, and the winding and unwinding system 100 can start to measure the winding diameter of the winding roller 120, optimizing the roll changing process and helping to improve production. efficiency.

According to some embodiments of the present application, the sensing device 150 may include a light-emitting device 151 and a receiving device 152. The light-emitting device 151 is used to emit photoelectric signals, and the receiving device 152 is used to receive photoelectric signals. The winding roller 120 located at a set position rotates a During the circle, the receiving state of the photoelectric signal of the receiving device 152 changes and sends an in-position signal.

For example, as shown in Figures 3 to 5, the light-emitting device 151 can be installed at one end of the winding roller 120 along the rotation axis, and rotate synchronously under the driving of the winding roller 120. Each time the winding roller 120 rotates, The photoelectric signal emitted by the light-emitting device 151 changes from being incident on the receiving device 152 to being incident on the receiving device 152. The receiving device 152 responds to the photoelectric signal by The in-position signal is sent from the non-receiving state to the receiving state. With this arrangement, the sensing device 150 is a photoelectric switch, which has the advantage of high detection accuracy.

According to other embodiments of the present application, the receiving device 152 may also be configured to send an in-position signal when the photoelectric signal changes from a receiving state to a non-receiving state. For example, the light-emitting device 151 and the receiving device 152 are fixed and relatively arranged, and a light-shielding member is installed on the rewinding roller 120 at a set position. The light-shielding member can rotate with the rewinding roller 120 to between the light-emitting device 151 and the receiving device 152. Block the photoelectric signal.

The light-shielding member can be installed on one end of the rewinding roller 120 along the rotation axis, and rotates synchronously under the driving of the rewinding roller 120. After the light-shielding member rotates with the rewinding roller 120, the light-shielding member rotates to the light-emitting device 151 and the receiving device. 152 and blocks the photoelectric signal, then the receiving device 152 changes from the receiving state to the non-receiving state for the photoelectric signal. Among them, the light-emitting device 151 and the receiving device 152 may be separate components. With this arrangement, the sensing device 150 sends out an in-position signal according to the rotation of the winding roller 120, and cooperates with the controller for measurement.

According to other embodiments of the present application, the sensing device 150 is a slot-type photoelectric switch or a through-beam photoelectric switch. Among them, the slot-type photoelectric switch has the advantages of low cost, fast response speed, and small space occupation.

By configuring the slot-type sensing device 150 as a slot-type photoelectric switch or a through-beam photoelectric switch, it can be easily obtained through purchase, and the light-emitting device 151 and the receiving device 152 are integrated into a single component, eliminating the need for separate installation. Of course, in other embodiments of the present application, the sensing device 150 can also be replaced by a Hall proximity switch or the like.

According to other embodiments of the present application, as shown in FIG. 5 , the rewinding and unwinding system 100 further includes a traction mechanism 160 , which is located upstream of the rewinding roller 120 along the conveying direction of the strip 200 to pull the strip. 200 is transported to the winding roller 120 located at the set position. By providing the traction mechanism 160 , the traction mechanism 160 is used to apply traction force to the strip 200 so as to pull the strip 200 and transport it in a direction close to the winding roller 120 .

According to other embodiments of the present application, when the rewinding and unwinding system 100 includes the technical solution of the traction mechanism 160, the traction mechanism 160 may specifically include a traction motor 163, an active traction roller 161 and a driven traction roller 162. The active traction roller 161 and The traction motor 163 is connected in transmission, and the strip 200 passes between the active traction roller 161 and the driven traction roller 162 . The measuring device 140 can determine the running length of the strip 200 by measuring the rotation angle or rotational displacement of the active traction roller 161 or the driven traction roller 162 .

It can be understood that when the diameters of the active traction roller 161 and the driven traction roller 162 are the same, the rotational displacement of the active traction roller 161 and the driven traction roller 162 is the running length of the strip 200 . For example, when the active traction roller 161 and the driven traction roller 162 rotate once, the running length of the strip 200 is the circumference of the active traction roller 161 and the driven traction roller 162 .

The measuring device 140 can directly measure the rotational displacement of the active traction roller 161 or the driven traction roller 162, or can measure the rotation angle of the active traction roller 161 or the driven traction roller 162, and then determine the rotational displacement based on the rotation angle. For example, the measuring device 140 may be a rotary encoder, which is provided on the active traction roller 161 or the driven traction roller 162 to detect the rotation angle of the traction roller; or the measurement device 140 may also be an angle sensor.

In some embodiments, the measuring device 140 can also be provided on the traction motor 163. The measuring device 140 is used to obtain the number of pulses of the traction motor 163. Based on the number of pulses, the rotation angle of the traction motor 163 can be determined. Based on the relationship between the traction motor 163 and the active traction The transmission ratio between the rollers 161 can determine the rotation angle of the active traction roller 161.

According to other embodiments of the present application, the measuring device 140 is a meter wheel, and the meter wheel is in contact with the surface of the active traction roller 161 or the driven traction roller 162 .

The rewinding and unwinding system 100 may also include a fixed base 141, a connecting rod 142 and a cylinder 143. One end of the connecting rod 142 is connected to the fixed base 141, the other end of the connecting rod 142 is connected to the meter wheel, and the cylinder 143 is fixedly installed on the fixed base 141. On the fixed base 141, the telescopic rod of the cylinder 143 is connected to the connecting rod 142. The telescopic rod of the cylinder 143 telescopes to drive the connecting rod 142 to move, so that the meter wheel can contact the active traction roller 161 or the driven traction roller 162.

As shown in Figure 4, taking the surface contact between the meter wheel and the driven traction roller 162 as an example, the principle of the measuring device 140 to measure the running length of the strip 200 is: the driven traction roller 162 rotates to pull the strip 200 to move, The meter wheel rotates as the driven traction roller 162 rotates to detect the rotational displacement of the driven traction roller 162, thereby directly determining the running length of the strip 200.

In this embodiment, the meter wheel is arranged to be in contact with the surface of the active traction roller 161 or the driven traction roller 162 to detect the rotational displacement of the active traction roller 161 or the driven traction roller 162, thereby directly determining the belt movement of the strip 200 Length, no conversion required, little calculation required.

Moreover, compared with the meter wheel contacting the surface of the strip 200 to measure the running length of the strip 200, in this embodiment the meter wheel does not contact the strip 200 to prevent the meter wheel from getting on the strip 200. The strip 200 is affected due to contact with the active material layer. It should also be noted that compared with the meter wheel being in contact with the winding roller 120 at the set position, by arranging the meter wheel to be in contact with the surface of the active traction roller 161 or the driven traction roller 162, the meter wheel is prevented from being The take-up roller 120 is influenced to take up the strip 200 .

According to some embodiments of the present application, continuing to refer to FIG. 3 , the rewinding and unwinding system 100 may also include a driving device 171 and a roll-changing pressure roller 170 . The roll-changing pressure roller 170 is drivingly connected to the driving device 171 , and the driving device 171 is connected to the control device 171 . device connection. When the winding diameter reaches the preset threshold, the controller sends a rolling signal to the driving device 171, and the driving device 171 Upon receiving the roll pressing signal, the roll changing pressure roller 170 is driven to move close to the set position, so that the roll changing pressure roller 170 contacts the strip 200 .

Among them, when the winding diameter reaches the preset threshold, the controller is not limited to sending the roll changing signal and the rolling signal at the same time. It can also send the rolling signal first and then send the rolling signal.

The circumferential surface of the winding roller 120 may also be provided with a glue layer. An exemplary working principle of the winding and unwinding system 100 in this embodiment is: when the winding diameter reaches a preset threshold, the controller first sends a roll changing signal to the roll changing device 130, and the roll changing device 130 receives the roll changing signal. The signal drives another winding roller 120 to move to the set position, and the other winding roller 120 can contact the strip 200 and start winding; the controller then sends a rolling signal to the driving device 171, and the driving device 171 receives the rolling signal. The signal drives the roll-changing pressure roller 170 to move close to the set position, so that the roll-changing pressure roller 170 contacts the strip 200. The roll-changing pressure roller 170 exerts pressure on the strip 200, so that the connection between the strip 200 and the adhesive layer is reliable. Ensure that the strip 200 can be wound onto the take-up roller 120 .

In this design, after the roll is changed, the new winding roller 120 winds up the strip 200, and the change pressure roller 170 can move to contact the strip 200 to exert pressure on the strip 200 to ensure that the strip 200 can be wound to On the new winding roller 120.

The driving device 171 can be configured to drive the roll-changing pressure roller 170 to move in the vertical direction. At this time, the driving device 171 receives the roll-pressing signal and can drive the roll-changing pressure roller 170 to move up a preset height to contact the strip 200. Afterwards, the driving device 171 can stop driving the roll changing pressure roller 170 to move upward.

In the related art, a contact sensor may be provided on the roll-changing pressure roller 170, and the driving mechanism stops when the contact sensor detects that the roll-changing pressure roller 170 is in contact with the strip 200, so as to prevent the driving mechanism from continuing to drive the roll-changing pressure roller 170 to move upward. The roll changing pressure roller 170 collides with the winding roller 120 . However, in this example, if the contact sensor fails, an accident may easily occur in which the roll changing pressure roller 170 and the winding roller 120 collide. In the rewinding and unwinding system 100 of this embodiment, the controller can control the driving mechanism to drive the roll-changing pressure roller 170 to move up to a preset height according to the measured rewinding diameter. When the roll-changing pressure roller 170 moves up to the preset height, To be in contact with the strip 200 , it is beneficial to reduce the risk of interference between the roll changing pressure roller 170 and the winding roller 120 , and the contact sensor is omitted, which is beneficial to reducing hardware costs.

According to some embodiments of the present application, the driving device 171 may be configured to include a swing arm 1712 and a servo motor 1711. One end of the swing arm 1712 is connected to the roll changing pressure roller 170, and the other end of the swing arm 1712 is drivingly connected to the servo motor 1711. Motor 1711 is connected to the controller.

The servo motor 1711 can drive the swing arm 1712 to rotate to drive the roll changing pressure roller 170 to rotate close to the set position and contact the strip 200 . In this embodiment, the controller can control the driving mechanism to drive the roll-changing pressure roller 170 to rotate at a preset angle based on the measured winding diameter. When the roll-changing pressure roller 170 rotates at the preset angle, it just contacts the strip 200 .

The rewinding and unwinding system 100 may also include a cutting device connected to the controller. When the strip 200 is wound onto the other rewinding roller 120, the controller may send a cutting signal to the cutting device, and the cutting device receives the The strip 200 wound between the two winding rollers 120 is cut off when the cutting signal is received. In this way, one of the winding rollers 120 completes winding, and the other winding roller 120 starts to wind the strip 200 .

Continuing to refer to FIG. 3 , the unwinding and unwinding system 100 may further include an unwinding roller 110 for unwinding the strip 200 . The unwinding roller 110 is located on the side of the winding roller 120 along the conveying direction of the strip 200 . upstream.

The rewinding and unwinding system 100 also includes a third motor 111, and the third motor 111 drives the unwinding roller 110 to rotate. The rotation direction of the unwinding roller 110 is the same as the rotation direction of the winding roller 120. The diameters of the unwinding roller 110 and the diameters of the winding roller 120 may be the same or different. The unwinding length of the unwinding roller 110 is the winding length of the winding roller 120 . It should be noted that when the diameter of the unwinding roller 110 is the same as the diameter of the winding roller 120, the sensing device 150 can also be replaced by sending an in-position signal when the unwinding roller 110 rotates once.

The rewinding and unwinding system 100 of this embodiment can measure the running length of the strip 200 when the rewinding roller 120 rotates once. Since the rotation direction of the unwinding roller 110 is the same as the rotation direction of the rewinding roller 120, it can be measured. The current unwinding radius of the unwinding roller 110 can then be used to calculate the number of layers of the strip 200 wound on the unwinding roller 110 .

Compared with the measurement of the winding diameter by an ultrasonic distance sensor, the measurement accuracy of the winding and unwinding system 100 of this embodiment is high. Therefore, it is helpful to avoid measuring the strip 200 wound on the unwinding roller 110 due to measurement errors. The number of layers is misestimated, thereby helping to avoid waste caused by automatic roll change of the unwinding roller 110 in advance.

An embodiment of the present application also provides a battery pole piece preparation device. The preparation device is used to manufacture battery pole pieces, and may include the rewinding and unwinding system 100 of any of the above embodiments. The preparation device can use the rolls of pole pieces and separators produced by the winding and unwinding system 100 to be rolled to form an electrode assembly.

Figure 9 is a schematic flow chart of a rewinding and unwinding control method according to an embodiment of the present application. Referring to FIG. 9 , an embodiment of the present application also provides a rewinding and unwinding control method, which is suitable for controlling the rewinding and unwinding system 100 of any of the above embodiments. The control method may include steps S101 to S103.

Step S101, obtain the in-position signal.

Step S102, in response to receiving the in-position signal, determine the winding diameter of the winding roller 120 located at the set position according to the tape running length measured by the measuring device 140.

Step S103: When the winding diameter reaches a preset threshold, a roll change signal is sent to the roll changing device 130 to control the roll changing device 130 to drive the other winding roller 120 to move to a set position and contact the strip 200, so that The strip 200 is wound onto the other of the take-up rollers 120 .

Using this control method to control the rewinding and unwinding system 100, the current circumference of the rewinding roller 120 can be determined by measuring the running length of the strip 200 when the rewinding roller 120 rotates once, and then the current circumference of the rewinding roller 120 can be measured. The winding diameter. In this way, the ultrasonic distance sensor is omitted, which not only saves costs, but also has high measurement accuracy, which helps avoid misestimation of the number of winding layers due to measurement errors. Moreover, the way the rewinding and unwinding system 100 of this embodiment measures the rewinding diameter has nothing to do with the thickness and tension of the strip 200. Therefore, it is not affected by the thickness of the pole piece and the interlayer spacing of the pole piece, and the measurement accuracy is high. .

After executing step S102, as shown in Figure 9, the control method may further include step S104.

Step S104: When the winding diameter reaches a preset threshold, a rolling signal is sent to the driving device 171 to control the driving device 171 to drive the roll-changing pressure roller 170 to move close to the set position, so that the roll-changing pressure roller 170 and the strip 200 touch.

Here, the roll pressing signal and the roll changing signal can be sent at the same time, or the roll changing signal can be sent first and then the roll pressing signal can be sent.

Designed in this way, after using this control method to control the automatic roll change of the winding and unwinding system 100, the roll changing pressure roller 170 can be controlled to move to contact the strip 200 to exert pressure on the strip 200 to ensure that the strip 200 can be wound to On the new winding roller 120.

In addition, after executing step S104, the control method may further include step S105.

Step S105: Send a cutting signal to the cutting device to control the cutting device to cut the strip 200 wound between the two winding rollers 120. In this way, automatic roll changing is achieved.

Referring to FIGS. 3 and 4 , in a specific embodiment, the rewinding and unwinding system 100 may include: at least two rewinding rollers 120 , a roll changing device 130 , a light emitting device, a receiving device, a meter counting wheel, and a traction mechanism. 160 and controller, the traction mechanism 160 may specifically include a traction motor 163, an active traction roller 161 and a driven traction roller 162. The active traction roller 161 is drivingly connected to the traction motor 163, and the strip 200 is composed of an active traction roller 161 and a driven traction roller. After passing between 162, the meter wheel is in contact with the surface of the driven traction roller 162.

The roll changing device 130 can drive at least two rewinding rollers 120 to move to the set position in sequence. The rewinding roller 120 located at the set position can rewind the strip 200. Each rewinding roller 120 is provided with a light shield at one end along the rotation axis. After the light-shielding piece rotates with the winding roller 120, the light-shielding piece rotates to between the light-emitting device and the receiving device and blocks the photoelectric signal. The receiving device 152 sends an in-position signal to the controller, and the controller measures the value measured by the meter wheel. The running length of the strip 200 determines the circumference of one rotation of the winding roller 120 at the set position, and then calculates the winding diameter of the winding roller 120 at the set position.

When the winding diameter reaches the preset threshold, the controller sends a roll change signal to the roll change device 130. The roll change device 130 receives the roll change signal and drives the other winding roller 120 to move to the set position and interact with the strip 200. contact, so that the strip 200 is wound onto the other winding roller 120 .

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or substitutions do not deviate from the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present application. The scope shall be covered by the claims and description of this application. In particular, as long as there is no structural conflict, the technical features mentioned in the various embodiments can be combined in any way. The application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

A rewinding and unwinding system, including:

At least two take-up rollers;

A roll-changing device capable of driving the at least two rewinding rollers to move to a set position in sequence, and the rewinding roller located at the set position can rewind the strip;

A sensing device that sends an in-position signal when the winding roller at the set position rotates once;

A measuring device for measuring the running length of the strip;

A controller is connected to the sensing device, the measuring device and the roll changing device. In response to receiving the in-position signal, the controller determines the location based on the tape length measured by the measuring device. The winding roll diameter of the winding roller at the set position; the controller sends a roll changing signal to the roll changing device when the winding roll diameter reaches a preset threshold, and the roll changing device receives When the roll change signal drives the other of the winding rollers to move to the set position and contact the strip, so that the strip is wound onto the other of the winding rollers.
The rewinding and unwinding system according to claim 1, wherein the sensing device includes a light-emitting device and a receiving device, the light-emitting device is used to emit photoelectric signals, the receiving device is used to receive photoelectric signals, and is located in the setting When the winding roller rotates once in the position, the receiving device's receiving state of the photoelectric signal changes and sends the in-position signal.
The rewinding and unwinding system according to claim 2, wherein the light-emitting device and the receiving device are fixed and relatively arranged, and a light-shielding member is installed on the rewinding roller located at the set position, and the light-shielding member The winding roller can rotate to between the light-emitting device and the receiving device and block the photoelectric signal.
The rewinding and unwinding system according to any one of claims 1 to 3, wherein the sensing device is a slot-type photoelectric switch or a through-beam photoelectric switch.
The rewinding and unwinding system according to any one of claims 1 to 4, further comprising a traction mechanism located upstream of the rewinding roller along the conveying direction of the strip to traction the The strip is transported to the winding roller located at the set position.
The rewinding and unwinding system according to claim 5, wherein the traction mechanism includes a traction motor, an active traction roller and a driven traction roller, the active traction roller is drivingly connected to the traction motor, and the strip is driven by the passing between the active traction roller and the driven traction roller;

The measuring device determines the running length of the strip by measuring the rotation angle or rotational displacement of the active traction roller or the driven traction roller.
The rewinding and unwinding system according to claim 6, wherein the measuring device is a meter counting wheel, and the meter counting wheel is in contact with the surface of the active traction roller or the driven traction roller.
The rewinding and unwinding system according to any one of claims 1 to 7, further comprising a driving device and a roll changing pressure roller that is drivingly connected to the driving device, and the driving device is connected to the controller;

The controller sends a rolling signal to the driving device when the winding diameter reaches a preset threshold. The driving device receives the rolling signal and drives the roll changing pressure roller to move closer to the device. Position the roll changing pressure roller in contact with the strip.
The rewinding and unwinding system according to claim 8, wherein the driving device includes a swing arm and a servo motor, one end of the swing arm is connected to the roll changing pressure roller, and the other end of the swing arm is connected to the The servo motor is drivingly connected, and the servo motor is connected with the controller.
The rewinding and unwinding system according to any one of claims 1 to 9, further comprising an unwinding roller, the unwinding roller is used to unwind the strip, and the unwinding roller is used to unwind the strip along the conveying direction of the strip. The unwinding roller is located upstream of the winding roller.
A device for preparing battery pole pieces, including the rewinding and unwinding system according to any one of claims 1-10.
A rewinding and unwinding control method, suitable for the rewinding and unwinding system according to any one of claims 1-10, including:

Get the position signal;

In response to receiving the in-position signal, determine the winding diameter of the winding roller located at the set position based on the tape length measured by the measuring device;

When the winding diameter reaches a preset threshold, a roll change signal is sent to the roll changing device to control the roll changing device to drive the other of the winding rollers to move to the set position and interact with the set position. The strips come into contact so that the strips are wound onto the other of the take-up rollers.
The rewinding and unwinding control method according to claim 12, wherein after the rewinding diameter of the rewinding roller located at the set position is determined based on the tape running length measured by the measuring device , the control method also includes:

When the winding diameter reaches a preset threshold, a rolling signal is sent to the driving device to control the driving device to drive the roll changing pressure roller to move close to the set position, so that the roll changing pressure roller The rollers are in contact with the strip.